The basic physical systems of a country's or community's population, including roads, utilities, water, sewage, etc. These systems are considered essential for enabling productivity in the economy. Developing infrastructure often requires large initial investment, but the economies of scale tend to be significant.
Lesson Summary. Both phylogenetic trees and cladograms help show the relationships between different organisms, but only phylogenetic trees have branches that represent evolutionary time and amount of change. These were formerly based on physical characteristics, but are more accurately based on genetic relationships.iologists use cladograms and phylogenetic trees to illustrate relationships among organisms and evolutionary relationships for organisms with a shared common ancestor. Both cladograms and phylogenetic trees show relationships among organisms, how alike, or similar, they might be.
Evidence from morphological, biochemical, and gene sequence data suggests that all organisms on Earth are genetically related, and the genealogical relationships of living things can be represented by a vast evolutionary tree, the Tree of Life.